As a method of implementing the adjustment of the supply and demand of electric power in a power grid to date, a method has been adopted that gives priority to the use of the output control function of a thermal power generator of a thermal generation plant combined as appropriate with the output adjustment function of pumping-up electrical power generation.
In the future, however, with the widespread incorporation in power grids of renewable power sources as decentralized power sources, as represented by photovoltaic power generation and wind power generation for which the amount of power generation depends on the weather, the fluctuation of output of these decentralized power sources raises the concern that the balance between supply and demand of electric power will be even more adversely affected than in the past. As a result, there is the danger that an electrical power supply and demand adjustment method that focuses on thermal power generators to compensate for variations in the balance between supply and demand of electric power that arise from decentralized power sources will not be up to the task. As a result, a more effective electric power supply and demand adjustment technology has become necessary to supplement electric power supply and demand adjustment methods that focus on thermal power generators.
Technology that utilizes decentralized energy storage (hereinbelow energy storage is abbreviated “ES”) such as “storage batteries” that are linked to the distribution network of a power grid holds promise as one electric power supply and demand adjustment technology that can meet this demand and that is expected to become extremely widespread in the future.
Patent Document 1 discloses a power grid control method that uses customer-side secondary batteries (ES) to implement adjustment of the supply and demand of electric power.
In the power grid control method disclosed in Patent Document 1, a power grid control device acquires the charged amount of the secondary batteries and further acquires from a central load dispatching office a schedule for supplying electric power to the power grid based on estimated electric power demand. The power grid control device determines the operation schedule of secondary batteries based on the charged amount of the secondary batteries and the electric power supply schedule.
Upon determining the operation schedule of the secondary batteries, the power grid control device transmits the operation schedule to the secondary battery control system that controls the operation of the secondary batteries.
The secondary battery control system, upon receiving the operation schedule from the power grid control device, controls the charging and discharging of the secondary batteries in accordance with the operation schedule regardless of the actual state of the power grid.
Patent Document 2 discloses a system in which a central controller acquires status information of a plurality of battery cells that have been sampled at the same time by way of local monitors or a higher-order controller.